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Sep 20, 2013
09/13

by
Ken'ichi Ohshika; Teruhiko Soma

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In this paper, we are concerned with hyperbolic 3-manifolds $\hyperbolic^3/G$ such that $G$ are geometric limits of Kleinian surface groups isomorphic to $\pi_1(S)$ for a finite-type hyperbolic surface $S$. In the first of the three main theorems, we shall show that such a hyperbolic 3-manifold is uniformly bi-Lipschitz homeomorphic to a model manifold which has a structure called brick decomposition and is embedded in $S \times (0,1)$. Conversely, any such manifold admitting a brick...

Source: http://arxiv.org/abs/1002.4266v1

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Sep 22, 2013
09/13

by
Fabio Baruffa; Peter Stano; Jaroslav Fabian

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The effects of spin-orbit coupling on the two-electron spectra in lateral coupled quantum dots are investigated analytically and numerically. It is demonstrated that in the absence of magnetic field the exchange interaction is practically unaffected by spin-orbit coupling, for any interdot coupling, boosting prospects for spin-based quantum computing. The anisotropic exchange appears at finite magnetic fields. A numerically accurate effective spin Hamiltonian for modeling spin-orbit-induced...

Source: http://arxiv.org/abs/0908.2961v2

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Sep 22, 2013
09/13

by
Yu-Ying Zhang; Nobuhiro Okabe; Alexis Finoguenov; Graham P. Smith; Rocco Piffaretti; Riccardo Valdarnini; Arif Babul; August E. Evrard; Pasquale Mazzotta; Alastair J. R. Sanderson; Daniel P. Marrone

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We compare X-ray hydrostatic and weak-lensing mass estimates for a sample of 12 clusters that have been observed with both XMM-Newton and Subaru. At an over-density of \Delta=500, we obtain 1-M^{X}/M^{WL}=0.01+/-0.07 for the whole sample. We also divided the sample into undisturbed and disturbed sub-samples based on quantitative X-ray morphologies using asymmetry and fluctuation parameters, obtaining 1-M^{X}/M^{WL}=0.09+/-0.06 and -0.06+/-0.12 for the undisturbed and disturbed clusters,...

Source: http://arxiv.org/abs/1001.0780v3

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Sep 20, 2013
09/13

by
N. Lazarides; G. P. Tsironis

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We have obtained exact analytical expressions in closed form, for the linear modes excited in finite and discrete systems that are driven by a spatially homogeneous alternating field. Those modes are extended for frequencies within the linear frequency band while they are either end-localized or end-avoided for frequencies outside the linear frequency band. The analytical solutions are resonant at particular frequencies, which compose the frequency dispersion relation of the finite system.

Source: http://arxiv.org/abs/1002.4328v1

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Sep 20, 2013
09/13

by
B. C. Low

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We demonstrate the Parker Magnetostatic Theorem in terms of a small neighborhood in solution space containing continuous force-free magnetic fields in small deviations from the uniform field. These fields are embedded in a perfectly conducting fluid bounded by a pair of rigid plates where each field is anchored, taking the plates perpendicular to the uniform field. Those force-free fields obtainable from the uniform field by continuous magnetic footpoint displacements at the plates have field...

Source: http://arxiv.org/abs/1002.4399v1

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Sep 20, 2013
09/13

by
Yidong Xu; Andrea Ferrara; Francisco S. Kitaura; Xuelei Chen

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We use a model developed by Xu et al. (2010) to compute the 21 cm line absorption signatures imprinted by star-forming dwarf galaxies (DGs) and starless minihalos (MHs). The method, based on a statistical comparison of the equivalent width (W_\nu) distribution and flux correlation function, allows us to derive a simple selection criteria for candidate DGs at very high (z >= 8) redshift. We find that ~ 18% of the total number of DGs along a line of sight to a target radio source (GRB or...

Source: http://arxiv.org/abs/1002.4356v1

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Sep 20, 2013
09/13

by
Arnaud Beauville

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A list of open problems on holomorphic symplectic, contact and Poisson manifolds.

Source: http://arxiv.org/abs/1002.4321v1

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Sep 20, 2013
09/13

by
Markku NihtilÃ¤

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In the design of quantum computing devices of the future the basic element is the qubit. It is a two-level quantum system which may describe population transfer from one steady-state to another controlled by a coherent laser field. A four-dimensional real-variable differential equation model is constructed from the complex-valued two-level model describing the wave function of the system. The state transition matrix of the model is constructed via the Wei-Norman technique and Lie algebraic...

Source: http://arxiv.org/abs/1002.4260v1

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Sep 17, 2013
09/13

by
Gregory C. Giecold

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The supergravity dual to N regular and M fractional D2-branes on the cone over \mathbb{CP}^3 has a naked singularity in the infrared. One can resolve this singularity and obtain a regular fractional D2-brane solution dual to a confining 2+1 dimensional N = 1 supersymmetric field theory. The confining vacuum of this theory is described by the solution of Cvetic, Gibbons, Lu and Pope. In this paper, we explore the alternative possibility for resolving the singularity - the creation of a regular...

Source: http://arxiv.org/abs/0912.1558v3

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Sep 20, 2013
09/13

by
M. A. Maize; M. A. Antonacci

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In this paper we derive an expression for the static electric polarizability of a particle bound by a finite potential well without the explicit use of the continuum states in our calculations. This will be accomplished by employing the elegant Dalgarno-Lewis perturbative technique.

Source: http://arxiv.org/abs/1002.4238v1

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Sep 21, 2013
09/13

by
Haixing Miao; Stefan Danilishin; Helge Muller-Ebhardt; Henning Rehbein; Kentaro Somiya; Yanbei Chen

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Significant achievements in the reduction of classical-noise floor will allow macroscopic systems to prepare nearly Heisenberg-Limited quantum states through a continuous measurement, i.e. conditioning. In order to probe the conditional quantum state and confirm quantum dynamics, we propose use of an optimal time-domain variational measurement, in which the homodyne detection phase varies in time. This protocol allows us to characterize the macroscopic quantum state below the Heisenberg...

Source: http://arxiv.org/abs/0905.3729v2

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Sep 20, 2013
09/13

by
Petros Souvatzis; Dominik Legut; Olle Eriksson; Mikhail I. Katsnelson

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Lattice dynamical methods used to predict phase-transformations in crystals typically evaluate the harmonic phonon spectra and therefore do not work in frequent and important situations where the crystal structure is unstable in the harmonic approximation, such as the $\beta$ structure when it appears as a high-temperature phase of the shape memory alloy (SMA) NiTi. Here it is shown by self consistent {\it ab initio} lattice dynamical calculations (SCAILD) that the critical temperature for the...

Source: http://arxiv.org/abs/1002.2482v2

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Sep 20, 2013
09/13

by
Xin Tong; Joey Paquet; Serguei A. Mokhov

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This paper presents the integration into the GIPSY of Lucx's context calculus defined in Wan's PhD thesis. We start by defining different types of tag sets, then we explain the concept of context, the types of context and the context calculus operators. Finally, we present how context entities have been abstracted into Java classes and embedded into the GIPSY system.

Source: http://arxiv.org/abs/1002.4392v1

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Sep 20, 2013
09/13

by
C. S. Withers; S. Nadarajah

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This paper extends Edgeworth-Cornish-Fisher expansions for the distribution and quantiles of nonparametric estimates in two ways. Firstly it allows observations to have different distributions. Secondly it allows the observations to be weighted in a predetermined way. The use of weighted estimates has a long history including applications to regression, rank statistics and Bayes theory. However, asymptotic results have generally been only first order (the CLT and weak convergence). We give...

Source: http://arxiv.org/abs/1002.4338v1

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Sep 20, 2013
09/13

by
Julien Langou

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A QR factorization of a tall and skinny matrix with n columns can be represented as a reduction. The operation used along the reduction tree has in input two n-by-n upper triangular matrices and in output an n-by-n upper triangular matrix which is defined as the R factor of the two input matrices stacked the one on top of the other. This operation is binary, associative, and commutative. We can therefore leverage the MPI library capabilities by using user-defined MPI operations and MPI_Reduce...

Source: http://arxiv.org/abs/1002.4250v1

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Sep 20, 2013
09/13

by
David Collins

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We describe a general framework for regarding oracle-assisted quantum algorithms as tools for discriminating between unitary transformations. We apply this to the Deutsch-Jozsa problem and derive all possible quantum algorithms which solve the problem with certainty using oracle unitaries in a particular form. We also use this to show that any quantum algorithm that solves the Deutsch-Jozsa problem starting with a quantum system in a particular class of initial, thermal equilibrium-based states...

Source: http://arxiv.org/abs/1002.4227v1

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Sep 20, 2013
09/13

by
Hiroyuki Osaka; Tamotsu Teruya

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Let $P \subset A$ be a inclusion of unital C*-algebras and $E\colon A \to P$ be a conditional expectation of index finite type. We introduce a Rokhlin property for $E$ and discuss about $\mathcal{D}$-absorbing proeprty, where $\mathcal{D}$ is a separable, unital, strongly self-absorbing C*-algebra. In this paper we consider permanent properties for strongly self-absorbing property under inclusions of unital C*-algebras with a finite Watatani index.

Source: http://arxiv.org/abs/1002.4233v1

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Sep 20, 2013
09/13

by
Margenstern Maurice

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In this paper, we significantly improve a previous result by the same author showing the existence of a weakly universal cellular automaton with five states living in the hyperbolic 3D-space. Here, we get such a cellular automaton with three states only.

Source: http://arxiv.org/abs/1002.4290v1

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Sep 20, 2013
09/13

by
Ashley Hobson; R. James Shank

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For a prime p>2 and q=p^n, we compute a finite generating set for the SL_2(F_q)-invariants of the second symmetric power representation, showing the invariants are a hypersurface and the field of fractions is a purely transcendental extension of the coefficient field. As an intermediate result, we show the invariants of the Sylow p-subgroups are also hypersurfaces.

Source: http://arxiv.org/abs/1002.4318v1

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Sep 20, 2013
09/13

by
D. S. Golubev; M. Marthaler; Y. Utsumi; Gerd Schon

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The intrinsic nonlinearity of Josephson junctions converts Gaussian current noise in the input into non-Gaussian voltage noise in the output. For a resistively shunted Josephson junction with white input noise we determine numerically exactly the properties of the few lowest cumulants of the voltage fluctuations, and we derive analytical expressions for these cumulants in several important limits. The statistics of the voltage fluctuations is found to be Gaussian at bias currents well above the...

Source: http://arxiv.org/abs/1002.4420v1

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Sep 20, 2013
09/13

by
Luigi Brugnano; Felice Iavernaro; Donato Trigiante

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One main issue, when numerically integrating autonomous Hamiltonian systems, is the long-term conservation of some of its invariants, among which the Hamiltonian function itself. Recently, a new class of methods, named Hamiltonian Boundary Value Methods (HBVMs) has been introduced and analysed, which are able to exactly preserve polynomial Hamiltonians of arbitrarily high degree. We here study a further property of such methods, namely that of having, when cast as a Runge-Kutta method, a matrix...

Source: http://arxiv.org/abs/1002.4394v1

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Sep 20, 2013
09/13

by
W. Chen; D. S. Goldbaum; M. Bhattacharya; P. Meystre

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We consider a cavity optomechanical system consisting of a Bose-Einstein condensate (BEC) interacting with two counterpropagating traveling-wave modes in an optical ring cavity. In contrast to the more familiar case where the condensate is driven by the standing-wave field of a high-$Q$ Fabry-P{\'e}rot cavity we find that both symmetric and antisymmetric collective density side modes of the BEC are mechanically excited by the light field. In the semiclassical, mean-field limit where the light...

Source: http://arxiv.org/abs/1002.4437v1

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Sep 20, 2013
09/13

by
Matthew P Young

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We give a short proof of Levinson's result that more than 1/3 of the zeros of the zeta function are on the critical line.

Source: http://arxiv.org/abs/1002.4403v1

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Sep 20, 2013
09/13

by
Olga S. Rozanova; Jui-Ling Yu; Chin-Kun Hu

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We propose a model based on the primitive system of the Navier-Stokes equations in a bidimensional framework as the $l$ - plane approximation, which allows us to explain the variety of tracks of tropical cyclones (typhoons). Our idea is to construct special analytical solutions with a linear velocity profile for the Navier-Stokes systems. The evidence of the structure of linear velocity near the center of vortex can be proven by the observational data. We study solutions with the...

Source: http://arxiv.org/abs/1002.4425v1

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Sep 20, 2013
09/13

by
Andreas Papaefstathiou; Jennifer M. Smillie; Bryan R. Webber

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We compute the resummed hadronic transverse energy (E_T) distribution due to initial-state QCD radiation in vector boson and Higgs boson production at hadron colliders. The resummed exponent, parton distributions and coefficient functions are treated consistently to next-to-leading order. The results are matched to fixed-order calculations at large E_T and compared with parton-shower Monte Carlo predictions at Tevatron and LHC energies.

Source: http://arxiv.org/abs/1002.4375v1

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Sep 21, 2013
09/13

by
Gentaro Watanabe

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For systems described by the two-site Bose-Hubbard Hamiltonian, we show that a sinusoidal modulation of the tunneling matrix element assists higher-order co-tunneling processes. Using this mechanism, we propose an efficient new scheme for creating a coherent superposition of states in which all particles are either on one site or all on the other site, the so-called NOON state. This scheme yields an almost perfect NOON state periodically. For larger numbers of particles, further reduction of...

Source: http://arxiv.org/abs/0901.3850v3

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Sep 20, 2013
09/13

by
Masaru Kada

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Iwasa investigated the preservation of various covering properties of opological spaces under Cohen forcing. By improving the argument in Iwasa's paper, we prove that the Rothberger property, the Menger property and selective screenability are also preserved under Cohen forcing and forcing with the measure algebra.

Source: http://arxiv.org/abs/1002.4419v1

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Sep 21, 2013
09/13

by
Dimitar Valev

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The astronomical observations indicate that the universe expands with acceleration and it has a finite event horizon. The recent CMB observations confirm the universe is homogeneous, isotropic and asymptotically flat. The total gravitational energy of a body having mass m is the gravitational potential energy originating from the gravitational interaction of the body with all masses of the universe, within the event horizon. The flat geometry of the universe enables to determine the total...

Source: http://arxiv.org/abs/0902.1412v3

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Sep 20, 2013
09/13

by
A. A. Abdo; for the Fermi-LAT Collaboration

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We present the first catalog of active galactic nuclei (AGN) detected by the LAT, corresponding to 11 months of data collected in scientific operation mode. The First LAT AGN Catalog (1LAC) includes 671 gamma-ray sources located at high Galactic latitudes (|b| > 10 deg) that are detected with a test statistic (TS) greater than 25 and associated statistically with AGNs. Some LAT sources are associated with multiple AGNs, and consequently, the catalog includes 709 AGNs, comprising 300 BL...

Source: http://arxiv.org/abs/1002.0150v2

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Sep 19, 2013
09/13

by
Kang-Sin Choi

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We study gauge symmetry in F-theory in light of global aspects. For this, we consider not only a simple (local) group, but also a semi-simple group with Abelian factors. Once we specify the complete gauge group by decomposing the discriminant, analogous to arranging 7-branes, we can derive the matter contents, their localization and the relation to enhanced groups. Global constraints coming from Calabi--Yau conditions and anomaly cancellations imply a unified group. The semisiple group shows...

Source: http://arxiv.org/abs/0910.2571v3

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Sep 20, 2013
09/13

by
M. KrÃ³likowska; P. A. DybczyÅ„ski

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The apparent source region (or regions) of long-period comets as well as the definition of the dynamically new comet are still open questions.The aim of this investigation is to look for the apparent source of selected long period comets and to refine the definition of dynamically new comets. We show that incorporation of the non-gravitational forces into the orbit determination process significantly changes the situation. We determined precise non-gravitational orbits of all investigated...

Source: http://arxiv.org/abs/1002.4397v1

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Sep 20, 2013
09/13

by
V. Mainieri; C. Vignali; A. Merloni; F. Civano; S. Puccetti; M. Brusa; R. Gilli; M. Bolzonella; A. Comastri; G. Zamorani; M. Aller; M. Carollo; C. Scarlata; M. Elvis; T. L. Aldcroft; N. Cappelluti; G. Fabbiano; A. Finoguenov; F. Fiore; A. Fruscione; A. M. Koekemoer; T. Contini; J. P. Kneib; O. Le Fevre; S. Lilly; A. Renzini; M. Scodeggio; S. Bardelli; A. Bongiorno; K. Caputi; G. Coppa; O. Cucciati; S. de la Torre; L. de Ravel; P. Franzetti; B. Garilli; A. Iovino; P. Kampczyk; C. Knobel; K. Kovac; F. Lamareille; J. F. Le Borgne; V. Le Brun; C. Maier; M. Mignoli; R. Pello; Y. Peng; E. Perez Montero; E. Ricciardelli; J. D. Silverman; M. Tanaka; L. Tasca; L. Tresse; D. Vergani; E. Zucca; P. Capak; O. Ilbert; C. Impey; M. Salvato; N. Scoville; Y. Taniguchi; J. Trump

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Using Chandra observations we have identified a sample of seven off-nuclear X-ray sources, in the redshift range z=0.072-0.283, located within optically bright galaxies in the COSMOS Survey. Using the multi-wavelength coverage available in the COSMOS field, we study the properties of the host galaxies of these ULXs. In detail, we derived their star formation rate from H_alpha measurements and their stellar masses using SED fitting techniques with the aim to compute the probability to have an...

Source: http://arxiv.org/abs/1002.4299v1

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Sep 19, 2013
09/13

by
Hisayuki Hara; Satoshi Aoki; Akimichi Takemura

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We study Markov bases of decomposable graphical models consisting of primitive moves (i.e., square-free moves of degree two) by determining the structure of fibers of sample size two. We show that the number of elements of fibers of sample size two are powers of two and we characterize primitive moves in Markov bases in terms of connected components of induced subgraphs of the independence graph of a hierarchical model. This allows us to derive a complete description of minimal Markov bases and...

Source: http://arxiv.org/abs/math/0701429v3

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Sep 20, 2013
09/13

by
Kimball Martin

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We give an exposition of central value formulas for twisted L-functions for GL(2) in terms of compact periods, with a focus on explaining an approach via the relative trace formula and joint work of the author with David Whitehouse.

Source: http://arxiv.org/abs/1002.4430v1

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Sep 20, 2013
09/13

by
Tom Bridgeland

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We give an introduction to Joyce's construction of the motivic Hall algebra of coherent sheaves on a variety M. When M is a Calabi-Yau threefold we define a semi-classical integration map from a Poisson subalgebra of this Hall algebra to the ring of functions on a symplectic torus. This material will be used in arxiv:1002.4374 to prove some basic properties of Donaldson-Thomas curve-counting invariants on Calabi-Yau threefolds.

Source: http://arxiv.org/abs/1002.4372v1

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Sep 20, 2013
09/13

by
Felix Rueting; Hannes Uecker

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We develop a numerical method for approximating the surface modes of sphere-like nanoparticles in the quasi-static limit, based on an expansion of (the angular part of) the potentials into spherical harmonics. Comparisons of the results obtained in this manner with exact solutions and with a perturbation ansatz prove that the scheme is accurate if the shape deviations from a sphere are not too large. The method allows fast calculations for large numbers of particles, and thus to obtain...

Source: http://arxiv.org/abs/1002.4337v1

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Sep 21, 2013
09/13

by
Vyacheslav Boyko; Jiri Patera; Roman Popovych

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A new purely algebraic algorithm is presented for computation of invariants (generalized Casimir operators) of Lie algebras. It uses the Cartan's method of moving frames and the knowledge of the group of inner automorphisms of each Lie algebra. The algorithm is applied, in particular, to computation of invariants of real low-dimensional Lie algebras. A number of examples are calculated to illustrate its effectiveness and to make a comparison with the same cases in the literature. Bases of...

Source: http://arxiv.org/abs/math-ph/0602046v3

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Sep 20, 2013
09/13

by
Tameem Albash

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We consider the dynamics of a probe fermion charged under a U(1) Maxwell field and a two form potential $B_{(2)}$ in a five dimensional gravity background. The gravity background is constructed from a new solution we find of type IIB supergravity. This new solution is expected to be dual to non-commutative Yang-Mills theory in the 't Hooft limit with global U(1) currents. We study the zero frequency, near horizon behavior of the fermion, where the equations of motion reduce to that of two...

Source: http://arxiv.org/abs/1002.4431v1

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Sep 20, 2013
09/13

by
Stefano De Leo; Pietro Rotelli

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We present the results of the planar diffusion of a Dirac particle by step and barrier potentials, when the incoming wave impinges at an arbitrary angle with the potential. Except for right-angle incidence this process is characterized by the appearance of spin flip terms. For the step potential, spin flip occurs for both transmitted and reflected waves. However, we find no spin flip in the transmitted barrier result. This is surprising because the barrier result may be derived directly from a...

Source: http://arxiv.org/abs/1002.4324v1

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Sep 20, 2013
09/13

by
Joss Bland-Hawthorn; Mark Krumholz; Ken Freeman

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The Galactic disk retains a vast amount of information about how it came to be, and how it evolved over cosmic time. However, we know very little about the secular processes associated with disk evolution. One major uncertainty is the extent to which stars migrate radially through the disk, thereby washing out signatures of their past (e.g. birth sites). Recent theoretical work finds that such "blurring" of the disk can be important if spiral arms are transient phenomena. Here we...

Source: http://arxiv.org/abs/1002.4357v1

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Sep 20, 2013
09/13

by
Mehmet Orhon

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Let $E$ be a Banach lattice. Its ideal center $Z(E)$ is embedded naturally in the ideal center $Z(E')$ of its dual. The embedding may be extended to a contractive algebra and lattice homomorphism of $Z(E)"$ into $Z(E')$. We show that the extension is onto $Z(E')$ if and only if $E$ has a topologically full center. (That is, for each $x\in E$, the closure of $Z(E)x$ is the closed ideal generated by $x$.) The result can be generalized to the ideal center of the order dual of an Archimedean...

Source: http://arxiv.org/abs/1002.4346v1

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Jul 20, 2013
07/13

by
Sean B. Gryb

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Jacobi's action principle is known to lead to a problem of time. For example, the timelessness of the Wheeler-DeWitt equation can be seen as resulting from using Jacobi's principle to define the dynamics of 3-geometries through superspace. In addition, using Jacobi's principle for non-relativistic particles is equivalent classically to Newton's theory but leads to a time-independent Schrodinger equation upon Dirac quantization. In this paper, we study the mechanism for the disappearance of time...

Source: http://arxiv.org/abs/0804.2900v3

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Sep 22, 2013
09/13

by
Laura Facchini

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We prove an analogue of Clifford's inequality for tropical curves. Next we focus on the hyperelliptic case and we characterize divisors attaining equality. Finally we speculate whether inequality in tropical Clifford's Theorem does imply hyperellipticity, in analogy with the classical case.

Source: http://arxiv.org/abs/1001.3249v2

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Sep 20, 2013
09/13

by
R. Crowston; G. Gutin; M. Jones; E. J. Kim; I. Z. Ruzsa

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In the problem Max Lin, we are given a system $Az=b$ of $m$ linear equations with $n$ variables over $\mathbb{F}_2$ in which each equation is assigned a positive weight and we wish to find an assignment of values to the variables that maximizes the excess, which is the total weight of satisfied equations minus the total weight of falsified equations. Using an algebraic approach, we obtain a lower bound for the maximum excess. Max Lin Above Average (Max Lin AA) is a parameterized version of Max...

Source: http://arxiv.org/abs/1002.0286v2

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Sep 20, 2013
09/13

by
Levi Lopes de Lima; Newton Luis Santos

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It is shown that the space of infinitesimal deformations of 2k-Einstein structures is finite dimensional at compact non-flat space forms. Moreover, spherical space forms are shown to be rigid in the sense that they are isolated in the corresponding moduli space.

Source: http://arxiv.org/abs/1002.4387v1

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Sep 18, 2013
09/13

by
Debashish Bose; C. P. Anil Kumar; R. Krishnan; Shobha Madan

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In this paper we prove the "Tiling implies Spectral" part of Fuglede's paper for the case of three intervals. Then we prove the "Spectral implies Tiling" part of the conjecture for the case of three equal intervals as also when the intervals have lengths 1/2, 1/4, 1/4. For the general case we change our approach to get information on the structure of the spectrum for the n-interval case. Finally, we use symbolic computations on Mathematica, and prove this part of the...

Source: http://arxiv.org/abs/0803.0049v2

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Sep 20, 2013
09/13

by
Heiko Gimperlein; Bernhard Kroetz; Henrik Schlichtkrull

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In this article a general framework for studying analytic representations of a real Lie group G is introduced. Fundamental topological properties of the representations are analyzed. A notion of temperedness for analytic representations is introduced, which indicates the existence of an action of a certain natural algebra A(G) of analytic functions of rapid decay. For reductive groups every Harish-Chandra module V is shown to admit a unique tempered analytic globalization, which is generated by...

Source: http://arxiv.org/abs/1002.4345v1

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27

Sep 20, 2013
09/13

by
V. Antonuccio-Delogu; J. Silk

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We study the internal circulation within the cocoon carved out by a relativistic jet emanating from an AGN, first developing model and then validating it using a series of numerical simulations. We notice that a significant increase of in this flow arises because gradients in the density and entropy develop near the hot spot, as a consequence of Crocco vorticity theorem. We find simple solutions for the streamlines, and we use them to predict the mass inflow rates towards the central regions....

Source: http://arxiv.org/abs/1002.4021v2

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Sep 22, 2013
09/13

by
Nobuhiro Uekusa

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Relations between bulk mass parameters for fermions propagating in higher dimensions are studied in analogy with the empirical mass relation for charged leptons. Masses of three generation of four-dimensional charged leptons are achieved from the bulk mass parameters of the same-order values. We find that the observed pattern of charged lepton mass spectrum is accommodated approximately in a set of simple relations for bulk and physical masses.

Source: http://arxiv.org/abs/0908.0372v2

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Sep 19, 2013
09/13

by
S. Dev; Surender Verma; Shivani Gupta

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We present a comprehensive phenomenological analysis of the allowed hybrid textures of neutrinos. Out of a total of sixty hybrid textures with one equality between the elements of neutrino mass matrix and one texture zero only twenty three are found to be viable at 99% C.L. whereas the earlier analysis found fifty four to be viable. We examine the phenomenological implications of the allowed hybrid textures including Majorana type CP-violating phases, 1-3 mixing angle and Dirac type...

Source: http://arxiv.org/abs/0909.3182v3